THE new 2007 Zagat Survey poses a riddle: How can the “average estimated cost” of dinner with one drink and tip at Eleven Madison Park be a mere $66 when this splendid restaurant’s least expensive dinner option is $76 without drink or tip? Answer: When you include a bar menu that has listed such items as a $12 baby pizza and $15 smoked salmon in the equation.

Although the 2007 edition has a new color map and the commendable inclusion of last-minute chef changes, Zagat is still low-balling prices – sometimes to a ridiculous degree.

This matters because even diners who don’t give a fig for the book’s ratings rely on its factual content – especially its accurate and unparalleled compilation of addresses, phone numbers and Web sites.

Many of us suspect the survey’s ratings for food, service and décor represent nothing more or less than the minced musings of contributors eager to see their quotes in print (and to receive a free copy of the guide just for participating).

A number with a dollar sign in front of it, on the other hand, looks mighty concrete. Yet in the Zagat world, a stew of fudge factors makes its price estimates as subjective as whether one liked the chicken.

The new survey’s introduction admirably points out that prices have dramatically risen across the board – by a whopping 14.5 percent at the 20 priciest places.

But although Zagat has made a sincere effort to address criticisms made in these pages last year, many figures given as the “average estimate of the price of a dinner with one drink and tip” at specific restaurants still seem more like cheapest-case scenarios than averages – if not utter flights of fancy.

At Gramercy Tavern, the book’s No. 1 favorite, the estimate for dinner with drink and tip is given as $76. In fact, that’s the price of the cheapest, mandatory prix-fixe -without drink or tip – and supplements or tasting menus will swell that considerably.

The only way to spend as little as $76 at dinner at Gramercy Tavern is to eat in the bar room, where the menu with choices as cheap as $10 is a la carte and no reservations are taken. Zagat mentions the bar option but does not explain that its $76 estimate is meant to be an average of the two quite different experiences.

The figure given for another perennial Zagat favorite, Gotham Bar & Grill, is $70. But with first courses averaging $20, entrees $38 and desserts $12, you’ve already gone through $70 without drink or tip; add them in, and you’re flirting with $100 a head for three courses.

The 2007 survey says the cost figure “reflects our surveyors’ average estimate of the price of a dinner with one drink and tip and is a benchmark only. Lunch is usually 25 percent less.” (Italics indicate language new to the guide this year.)

That fuzzy language at least allows wiggle room for a la carte menus, where a diner can theoretically order a single course or the cheapest options available.

But there’s no wiggle room where dinner is prix-fixe only.

At Eleven Madison Park, the survey’s 14th most popular place, dinner with one drink and tip easily costs $100, compared to Zagat’s $66 estimate – for a table of four that’s a whopping $136 difference.

Nor does it explain the $93 “estimate” at Chanterelle, No. 17 in popularity, where the mandatory prix-fixe (again, without drink or tip) starts at $95; or at Oceana, where the mandatory prix-fixe starts at $78, compared with Zagat’s alleged $77.

Publisher Tim Zagat explains the $66 “estimate” at Eleven Madison Park by saying, “The bar area is a la carte and averages roughly $40 a person. Also, the prix fixe was added in late April after the survey was under way.”

Eleven Madison Park’s “cocktail” area indeed offers an a la carte menu at night, with a limited selection from the dining room menu as well as cheaper bar snacks.

So do many other pricey places. In noting they’re an option, Zagat has a point – but only up to a point. Most people who consult the survey expect the listing to apply to the dining room, not a bar or lounge with a discounted or abbreviated menu.

And it’s scary to learn that at least some survey contributors are bar nibblers who might have no experience of the actual restaurant.

Of the places where the difference between the book’s estimate and the prix-fixe was less than at Eleven Madison Park, Zagat says, “They may be out of whack for a drink and tip, but it’s not a huge difference. People who go to Oceana or Chanterelle know they’re going to an expensive restaurant.”

Zagat says he’ll correct any errors in the next printing and consider adding a “prix-fixe only” designation in future editions.

But if even some survey participants base their ratings on bar snacks, I don’t want their two cents – which is a lot less than you’ll spend to make up the difference between what Zagat says you’ll pay and what you will pay.

“Simplicity reigns supreme” at David and Karen Waltuck’s 28-year-old TriBeCa “treasure”, a “paragon” of “luxurious dining” with “knockout” French cooking, “graceful” service that “never skips a beat” and a “lovely”, understated room with “pin-drop quiet” and “ample table spacing”; all this “joy” comes with a “premium price tag”, leading bargain-hunters to tout the “unbeatable” $42 prix fixe lunch.

Again voted No. 1 for Popularity, this Flatiron “standard bearer” via Danny Meyer “seems to get better every year”, offering an “extraordinary” New American menu, “comfortably elegant” surroundings and “impeccable service”; in short, it’s a “fabulous space to spend a bundle”, though regulars report you’ll find the “same quality” for less dough in the walk-in-friendly front room; N.B. Michael Anthony (ex Blue Hill at Stone Barns) is now overseeing the kitchen following the departure of founding chef Tom Colicchio.

This “sublime”, prix fixe-only East Midtown New American does “fearless and fantastic things” with “boat-fresh” seafood in “delightful” “luxury liner” like quarters, while the “caring” crew “treats every diner like an admiral”; N.B. the post-Surveydeparture of chef Cornelius Gallagher places the above Food rating in question.